During the day, less than 1,200 AGL in class G airspace, the flight visibility requirements are ½ statue mile and the cloud clearance requirements are to remain clear of clouds.
At night, less than 1200 AGL in Class G airspace, the helicopter flight visibility requirements are 1 statue mile visibility and cloud clearance requirements are to remain clear of clouds. However, within ½ mile of the runway or helipad of intended landing, a helicopter may be operated in an airport traffic pattern clear of clouds if the flight visibility is not less than ½ statue mile.
Reference(s):
14 CFR 91.155 Basic VFR weather minimums